off topic but insulation question

[iceman]

i currently have about 6 inches of blown in insulation..... i know insulating helps ..but if i add say 10 inches plus or whatever it takes to bring it to r49 will it really make THAT much of a diiference? or would it be a sublte diff?
i know its best to insulate but is it gonna keep my house at 75 degrees using less wood or keep it there say 3hrs longer????

 

[rob bennett]

Have a look at this site http://hes.lbl.gov/hes/db/zip.shtml
It will take a while to insert all of the info, but when you are done it will tell you the rate on investment of various home energy upgrades. I bet it will convince you that r49 is the way to go. For my house, upgrading to r 49 will pay for itself in 2.5 years after that its a considerable savings.

If you are going to blow anything up there go deep so you never have to go up there and step through your ceiling!

 

[dave11]

Well, I'd step back a bit before going ahead with more attic insulation, as it might not be the best use of your money. If you have six inches of blown cellulose, and it was installed properly, you have about R20 already. Not great but not terrible. But what R-value is in your walls? They're just as important, far as heat loss via conduction goes, maybe even more so, as they have more total area. Also, are there any sources of air leakage into the attic that can be filled-in, which should be most or all of them. This one is actually the biggest waster of heat in the average home.

Addressing either of these would be better use of the same money. If any of your walls are below R20, and can be brought up to that amount, the money is better spent there.

It is true that each additional increase in R-value gives less and less benefit. The benefit of going from R=1 to R=20 is huge. The value of going from R=20 to R=40 is much less.

 

[flewism]

My home is 2000sqft 1/3 on a crawlspace 2/3 with a full basement. I added 12 more inches of insulation 3 years ago bring for to a total of about 18"- 20" in the attic. Also added 6" to the floor in the crawlspace area, none there prior , and 6" to the sills around the basement, one inch white foam there prior about a $1200 investment.
Results, since about 60-70% of our heat come from burning wood, not much change in the gas bill. The house holds heat much better and does not rely on the gas furnace as much to heat the bedrooms as it had before. I can raise the temperature in the bedrooms, without cooking out the kitchen/family room where the stove is located on the other end of the house. Right now it is 32 degrees outside, it is 78 degrees in my kitchen/ family room and 71 degrees in the hallway down by the bedrooms and the furnace has not been on yet this year.

The biggest savings money wise is in my air conditioning bill in the summer about $40-50 a month less.
We upgraded the windows about 5 years ago, this house still has it's original 4" wall insulation, the house was built in 1990
This house is out in the open, and gets pounded by the weather all year long.
At first I was disappointed with the results of this investment, but after a few years I'm pleased that I did it.